Some bacteria produce electricity naturally, but to control the current the team had to engineer some new genetic circuitry.

One possible use: These bacteria could sense changes in chemical composition to monitor water quality. They would then convey the changes to a computer by shifts in electrical output.

National Yang Ming University of Taipei, Taiwan's BacToKidney project presented a bacteria that could serve as an internal dialysis machine for people suffering from chronic kidney failure.

The organism, which could work as a capsule delivered through the stomach to the small intestine, "could improve the quality of life of people suffering from chronic renal failure, who are often bound to dialysis machines," team member Chun-Ju Yang said.

Contributions from two other finalists may give researchers groundbreaking new tools to expand the realm of what's possible in synthetic biology.

The University of California, Berkeley, team's Clonebots project employs parts to help synthetic biologists develop other parts.

The University of Freiburg, Germany, team created a system to control certain proteins key to the formation of multicellular organisms. Their work could eventually help scientists to program cells to perform a variety of functions.

Quest for a Cure

The Grand Prize winners, from Slovenia, may have developed something with much more immediate human impact—a vaccine against the bacteria Helicobacter pylori.

The bacterium infects about half the world's population and is particularly prevalent in the developing world. Though many of the infected show no symptoms, others develop peptic ulcer disease or one of several types of cancer.

They team has already produced two vaccines and begun testing them on lab mice. One vaccine modifies the bacterium to make it "visible" to the immune system; the other makes the immune response more efficient.

Summing up this year's achievements, MIT researcher Randy Rettberg, iGEM's director, said the question that launched the competition five years ago has, happily, become moot.

"Can simple biological systems be built from standard, interchangeable parts and operated in living cells?" he asked. "Or is natural biology too complicated and unique?